Colored photography



Patented Feb. 1, 1938 orrlcn oonoann rno'rooasrnr Oliver Arnold Townsendand Arthur Percival Masters Wellington, New Zealand,

assignors I to Tru colour Film limited, Wellington, New ,(Zealan nDrawing. Application November 22, 1935, Se-

1 No. 51,170. In New Zealand Decembe '5 Claims. (01. 101-149) Theinvention relates to the art of color photography, and is concerned withthe production of multi-colored photographs or pictures obtained byblending color images on' a single base.

The object of the invention, is to provide an improved process to beused in the production of multicolor photographs as aforesaid, whetherstill photographs or moving picture photographs, in order that saidphotographs may be obtained in a simpler manner than heretofore withoutsacriiicing fidelity of color and detail, as compared with photographsproduced by known and more elaborate processes. I

The process to be herein described, may be said to commence with thetreatment of a set of color record prints containing photographic silverimages, andv made in known manner by any suitable method, the presentinvention providing a novel and advantageousmode of proceeding from saidcolor record prints to secure final multicolored photographs orpictures.

The color record prints can be made on any suitably sensitizedphotopaper, celluloid or other base, capable of receiving any necessaryphotographic treatment accbrding to known practice, toproduce'photographic silver images as aforesaid.

The main feature of' the invention resides in dye-toning thephotographic silver image of a color record print with dye inassociation with a mordant, whereby the image is brought to a conditionsuch that color can be transferred therefrom to a separate surface by'c'pntact with the latter.

A further feature of the invention. is the utilization of the mordantand dye to result in building up cr -continuation of the image inrelief, thecolor being transferable from said relief to a separatesurface.

All of the images can be .dyetoned, and color transferred therefrom andblended on a separate surface, or'one of said images can be colored sothat color will not transfer therefrom, in which case color istransferred from the dye-toned images to the image from which color isnontransferable. V

Other features are; also involved in the invention, as will be apparentfrom the description 50 which follows and the claims appended hereto.

The improved process will first bedescrlbed as proceeding from a set oftwo positive color record prints made from two color selectivenegatives, both positive prints being printed to obtain the 55 necessarygradation and weight required to give the desired effect in the finalphotograph or picture. o r

The print produced from the red-yellow record negative is toned blue inan iron bath preferably as follows: i 5

Ferric chloride "milligrams" 300 Oxalic acid mllligrams- 900 Nitric acid-cubic centimetres 1.5

Water cubic centimetres" 142 1o Potassium vierricyanide "milligrams" 300Water--- -cubic centimetres-.. 142

In using, it is preferred to prepare (a) and (b) separately, and mixtogether, although it is pos- 15 sible to prepare the whole as a singlesolution.

Instead of using the aboveiron bath for blue toning the print from thered-yellow record nega-' tive, said print may be dyetoned as follows;

- The reduced or developed metallic silver image 20 of the print isfirst brought to a condition in whichitzwill be receptive to a dye ordyes during subsequent treatment; certain formulae already well known inphotographic bleaching being capable of being used for this purpose, asuitable 25 formula comprising cupric chloride or bromide, with orwithout acids such as acetic, nitric, hyv drochloric or the like in thefollowing proportlons:

Cupric chloride grams..

Acetic acid (optional) cubic centimetres" 1 to 1.5

ater cubic centimetres- 284 The optimum time for treatment in the bath35 just given is two minutes. The print is then treated inya bathcontaining 1o v so -in solution a suitable dye or dyes, and anintermediary agent which will cause the dye to attach sufllciently tothe conditioned or receptive image, 40 to build up a colored image foruse in the transvfereuce process as hereinafter described; the in--termediary agent may be what is known in chemistry as athio-aminocompound, especially one in which the sulphur'is in are-active condition, and in which one or more amino or substituted aminogroups remain free to enter into chemical reaction-'. Suitable suchintermediary'agents are thiocarbamide andv thiosinamine, whilst cysteinand thioacetamide have also been found capable of acting in the desiredmanner. 1

Dyes suitable for this blue bath are those known on the market under thetrade names Patent Blue L, or BL, other dyes also being available, I v

although a satisfactory result is obtained by using a bath compounded asfollows:-

Patent Blue L, or BL milligrams 150 Thiocarbamide milligrams to 150Water cubic centimetres 170 The bleached or conditioned image is allowedto come into contact or association with the dye solution, when the dyeor dyes attaches or attach to the image, it being found that contact orassociation of the latter with the bath for approximately 3 minutes' isadequate. The colored or dyed image is then washed until excess dye andother water soluble substances are sumciently removed.

Alternatively the bleached or conditioned image may first be treated ina bath of thiocarbamide or material that will act in a similar manner,and

in such case the next step would be to treat the image in the blue-dyebath either containing, or

not containing, the thiocarbamide or material that will act in a similarmanner.

A thiocarbamide bath without dye, can comprise thiocarbamide 50 to 200milligrams, and water 170 cubic centimetres.

The silver image of the print from the violet blue green yellow record,is then bleached or conditioned as before described, and is dye-tonedred-yellow, in a bath similar to thatdescribed for dye toning the printtaken from the ,red

yellow record, except of course that an appropriate dye or dyes is orare used.

In connection with the red-yellow dye-toning,

it is known that acid fuchsin among other dyes, if mixed in suitableproportions with a suitable yellow dye (for instance tartr'azine) willbe replaced in certain parts, thus giving a gradation of color fromblue-red, through crimson scarlet, to orange and yellow.

Although only two dyes are mentioned for redyellow dye toning, otherdyes may be used,. a satisfactory bath being as follows:--

Acid fuchsin milligrams Tartrazine do to 200 Th'iocarbamide do Watercubic centimetres 1'10 The proportions and dilution of the.last-mentionedbath-or solution, may be varied according tocircumstances, and with different dyes more or less thiocarbamide orlike substance is desirable.

While for general dye toning purposes the ingredients of this red-yellowdye toning bath, with or without additions, may be considerably altered,the formula as given with the dyes mentioned, besides dye toning in theusual sense,

causes the continuation of deposition of color material beyond thatactually toning the image itself, so as to form in relief, an imagewhich facilitates transference of. color from the image as will be laterdescribed.

It is found that the use of certain image bleaching or conditioningagents, for the purpose of bringing the images into condition for dyetoning, if followed by the use of certain dyes when dye toning the'prints, results in a staining or coloring of the print with a lightershade of the color ,used, and said lighter shade is capable of beingutilized ,to extend the color range of the prints. For example, whencupric chloride is used to bleach or condition the images prior to dyetoning, andalthough other bleaching or conditioning agents may be used,those agents containing copper have the advantage that there 1 resultsduring dye toning, a staining of the gelatine of the emulsion by theacid fuchsin, and although said stain becomes decolorized during washingafter dye toning, it may be revived or made apparent as will be laterdescribed.

The next step is to combine color from, or-of, the colored images of thetwo positive prints, on the one base, and if an iron blue toned printfrom which color is not transferable is used, said print ,is firstimmersed in a bath containing a suitable salt such as potassium bromide,with or without an acid, the following bath for example, having beenfound suitable:-

Potassium bromide grams -5 Nitric acid (optional), -cubic centimetre" .1to .3 Water"; "cubic centimetres 284 The red yellow print is thenbrought so that its image registers accurately with the image of theblue toned print, following which the registering images of the printsare caused to make contact with each other, and are squeezed or pressedtogether, with the result that transference from the dye toned and builtup or relief image of the red-yellow print, takes place to the bluetoned print. As an aid to quick transference, heat and/or pressure maybe applied.

As an alternative, colorfrom the red-yellow print may be transferred tothe blueprint, after the latter has been immersed in the" bromide bath,but before said blue print is toned. After transfer of the'red-yellow-image, the blue print is then immersed in the blue toningbath, until it is suflicientlycolored, this treatment however, onlybeing carried out when the contents of the iron toning bath will notspoil color transferred from the red-yellow print.

-A still further alternative is that the blue.

print image may be blue dyeitoned as, described in connection with thedye toning of the redyellow print, instead of being iron blue toned, andtransference from both the blue and the redyellow dye toned print imagesmay be .made to Y a separate suitable surface, whether or not the latterhas any image, toned or untoned on it, and in such case after the firsttransference of color has been made, said surface is treated to fix thetransferred dye image, and prevent undue running' or retransfer tofurther prints which may subsequently be brought into contact therewith.

' Such a fixative bath can consist of acetic or other acid,thiocarbamide or other similar compound,

with or without such a salt as potassiumbromide or chrome alum, any ofthe following baths being suitable for the purpose:

Treatment in any of the aforesaid fixative baths, also has the effect ofexpanding a paper base back to the state it was in upon receivingthefirst physical color impression, this stretching treatment beingdesirable where a second transfer or impression is made to or .on aprint which has already received a transferred image.

The result obtained by carryingfout the before desirable,'such as in apink or mauve flower, it is I only necessary to treat the appropriateportions of the print with a suitable agent such as a dilute acid,oxalic acid 1%, or nitric acid being suitable for the purpose indicated,when the stain is immediately" revived, thus giving an approximate threecolor rendition from ,two negatives.

Where acid fuchsin or the like is used in redyellowdye toning, agents orreagents such as the above, may alsobe employed to brighten the reds.

Although a .cupric chloride bath, and an acid 'fuchsin bath have beenspecified to obtain a pink stain, the same process with other bleachingagents and other dye baths, may be employed application of a suitableagent such as dilute chlorine.

ammonia, sodium carbonate or asoluble sulphite, for the purpose ofremoving degrading matter. 3

Further, the yellow parts may be lightened or bleached by the use ofcertain chemicals such as The extra tones or shades" before referred to.may be brought up, and the yellows brightened or bleached, beforetransference of the colors.

Before or after transference, one or more of the prints may befixed byimmersion in any photographic fixing agent, such as hypo, provided itdoes not injuriously affect the color,

A further finishing effect treatment, may consist in immersion in adilute acid bath, before or after transference of color from an image.

The prints are then dried and mounted in any suitable manner. H

when three or more color separation negatives are employed, prints aremade from the negatives, and each printed to obtain the gradation andweight required to suit the particular color it represents, and to whichit is to be toned.

The silver images of the positive prints are then bleached orconditioned as. described in connection with the prints from the twocolor selective negatives, after which they are dyetoned, a separatecolor bath of the requisite color being used for each print. v y

An iron blue toning bat-h can be used instead of a blue dye bath ifdesired.

In transferring colors, if an iron blue toned print is used, the red andyellow, and other colored print images, are transferred to the iron bluetoned print which becomes the photograph or picture, or all of the printimages, if dye toned, may be transferred to any selected one of saidprints, or to any suitable separate surface with or without a tonedoruntoned image thereon.

The bringing up of the pink or other stain, and Y the brightening orlightening or bleaching of the yellow, or yellow color; and red or redcolor, may also be carried out when more than two neg-.-

atives and prints are employed, while all or such other of the remainingsteps used in the two color or two negative work, are also employedwhere necessary or desirable.

Should it be found that any one or more of t the print images to betransferred, owing to the astringency or softening characteristics ofthe different baths used for the respective prints,

has or have become slightly larger or smaller than the image'to whichtransference :is to be made, the print images may be brought to the samestate by placing a print or prints in a softening or hardening bath, oreven a cold or prints. this may be accomplished in several ways,

namely the iron blue toned print may, before or after other images aretransferred to it, be

placed in a developer, such as acid amidol where the silver ferrocyanideformed during blue toning is converted back to metallic silver, or othersuitable agent to form the required color image from the silverferrocyanide, provided such treat ment does not injure the blue toned orother. images.

In making final prints or pictures on a base havingan emulsion on eachside, an image is printed on each side of the base from the. differentcolor separation negatives, care being taken to see that the imagesregister, after which they are treated according to any necessary knownphotographic procedure.

Coloring or/and dyeing of the images is then carried out in the mannerand according to the description and directions before given, care beingtaken to prevent'color from one image detrimentally affecting the otherimage duringtreatment.

When the final print or picture is made on a,

base having an emulsion on one side only, a print is made from a colorseparation negative; developed, washed and colored or dyetoned in anappropriate color in the manner and according to the directions andinformation before given.

Thei film can then be treated according to known practice for thepurpose of receiving a further image, provided such treatment causes noinjury to the previously colored image.

'A print is then made from the complementary color separation negative,care being taken to see that registration is exact, following which thenewly printed image may be developed, fixed and washed, and followingwhich it is colored or dyetoned as before described.

When separate transparent bases to be combined to produce the finalprint or picture are used, each separate transparent base has a lightsensitive emulsion on one or both sides, each or any emulsion receivinga printed image from a color separation negative, the image if necessaryColor separation prints may also be obtained by using a multi-coloredscreen plate, or other colored negative, and'printing therefrom on t0separate surfaces, each of which is sensitized to receive a recordofselected rays, the prints obtained, if necessary, beingtreated as beforede- 4 scribedvfor transference of color to a, oomin'on base, whereby amulti-coior photograph or plcture'is produced.

. It is to be understood 1 that wnshing niid other steps well knowninjtheffarfltoi! photogrdphy ab thoughlnotfspeclflcally mentioned;n'reil ised when jthoughtinecessary ordesirnble. j 7, 2,1,1, V What'we.doclaimnn'd decirer'to obtin by Let-f ters Patent of theUmted-States orAmeric QisF-L 1. In transferring a second color. to iron blue base,thesteps of that bleaohing' a'nd then "buildingup thephotographic.silvertmage of a. v c g g,

. color record print with-Wain lth'ejpreseincey of: containing potassiumbromide flna llygpre s- I thiocarbamide andtransferrlngthecolortherefrom in the presence-of potassium bromide to the base bycontact'with the latter;-.

2. In transferring a second color to'an iron blue base, -the steps-of-flrst bleaching and then building up the photographic silver lmdgeof a color a separate color bath and transferring the color ,betransferred." g'

"therefrom in the presence of potassium bromide t he b s xcontw w h thet e it a im 'i t consisting injdyetoningfableg; ver"phototmocarpamidefindiyi thfite t ls' li m om d Pre sin e; ii s i nwhich [it is m be "transferred.

urra'ce' to T M m'akitig photographiccolor prints consisting indyetoning' n." ble ched sllve'r inmo- P1 image: v b u i i n aimns 15311! u d t 1 1 5 38 58? 11 ib m the image 'o'to gu n a-p whic 1; to

5; Method otmgking photoEIS-Phicnblorprints consisting in dyetoning ableached silver photo graphic image live solution containing 'Yanironblue dye; then in the presence ofpotassinm broit is to be transferred. iI,

' OLIVER ARNOLD TOWNSEND.

ARTHUR ,mlde, pressing the image onto a surface to'which

